A reflector assembly at a power beam receiver includes at least two sets of reflection surfaces positioned to shift some incoming light away from the center of the beam and towards the periphery. These surfaces may be positioned obliquely to one another, for example orthogonally. By shifting a portion of the power beam away from a higher-intensity center and toward a lower-intensity periphery, the reflector assembly may improve receiver efficiency without substantial redirection of power outside of a power-collecting surface of the receiver.